/**
  ******************************************************************************
  * @file    Examples_LL/RTC/RTC_Alarm_Init/Src/main.c
  * @author  MCD Application Team
  * @brief   This example code shows how to use STM32L1xx RTC LL API to configure
  *          an alarm.
  *          Peripheral initialization done using LL initialization function.
  ******************************************************************************
  * @attention
  *
  * <h2><center>&copy; Copyright (c) 2017 STMicroelectronics.
  * All rights reserved.</center></h2>
  *
  * This software component is licensed by ST under BSD 3-Clause license,
  * the "License"; You may not use this file except in compliance with the
  * License. You may obtain a copy of the License at:
  *                        opensource.org/licenses/BSD-3-Clause
  *
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "main.h"

/** @addtogroup STM32L1xx_LL_Examples
  * @{
  */

/** @addtogroup RTC_Alarm_Init
  * @{
  */

/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/
/* Oscillator time-out values */
#define LSI_TIMEOUT_VALUE          ((uint32_t)2)     /* 2 ms */
#define LSE_TIMEOUT_VALUE          ((uint32_t)5000)  /* 5 s */

/* Defines related to Clock configuration */
/* Uncomment to enable the adequate Clock Source */
#define RTC_CLOCK_SOURCE_LSI
/*#define RTC_CLOCK_SOURCE_LSE*/

#ifdef RTC_CLOCK_SOURCE_LSI
/* ck_apre=LSIFreq/(ASYNC prediv + 1) with LSIFreq=37 kHz RC */
#define RTC_ASYNCH_PREDIV          ((uint32_t)0x7F)
/* ck_spre=ck_apre/(SYNC prediv + 1) = 1 Hz */
#define RTC_SYNCH_PREDIV           ((uint32_t)0x122)
#endif

#ifdef RTC_CLOCK_SOURCE_LSE
/* ck_apre=LSEFreq/(ASYNC prediv + 1) = 256Hz with LSEFreq=32768Hz */
#define RTC_ASYNCH_PREDIV          ((uint32_t)0x7F)
/* ck_spre=ck_apre/(SYNC prediv + 1) = 1 Hz */
#define RTC_SYNCH_PREDIV           ((uint32_t)0x00FF)
#endif

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Buffers used for displaying Time and Date */
uint8_t aShowTime[50] = {0};
uint8_t aShowDate[50] = {0};

#if (USE_TIMEOUT == 1)
uint32_t Timeout = 0; /* Variable used for Timeout management */
#endif /* USE_TIMEOUT */

/* Private function prototypes -----------------------------------------------*/
void     SystemClock_Config(void);
void     Configure_RTC(void);
void     Configure_RTC_Alarm(void);
void     Show_RTC_Calendar(void);
void     LED_Init(void);
void     LED_On(void);
void     LED_Blinking(uint32_t Period);

/* Private functions ---------------------------------------------------------*/

/**
  * @brief  Main program
  * @param  None
  * @retval None
  */
int main(void)
{
  /* Configure the system clock to 32 MHz */
  SystemClock_Config();

  /* Initialize LED2 */
  LED_Init();

  /*##-1- Configure the RTC peripheral #######################################*/
  Configure_RTC();

  /*##-2- Configure Alarm ####################################################*/
  /* Configure RTC Alarm */
  Configure_RTC_Alarm();

  /* Infinite loop */
  while (1)
  {
    /*##-3- Display the updated Time and Date ################################*/
    Show_RTC_Calendar();
  }
}

/**
  * @brief  Configure RTC.
  * @param  None
  * @retval None
  */
void Configure_RTC(void)
{
  LL_RTC_InitTypeDef rtc_initstruct;
  
  /*##-1- Enables the PWR Clock and Enables access to the backup domain #######*/
  /* To change the source clock of the RTC feature (LSE, LSI), you have to:
     - Enable the power clock
     - Enable write access to configure the RTC clock source (to be done once after reset).
     - Reset the Back up Domain
     - Configure the needed RTC clock source */
  LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_PWR);
  LL_PWR_EnableBkUpAccess();
  
  /*##-2- Configure LSE/LSI as RTC clock source ###############################*/
#ifdef RTC_CLOCK_SOURCE_LSE
  /* Enable LSE only if disabled.*/
  if (LL_RCC_LSE_IsReady() == 0)
  {
    LL_RCC_ForceBackupDomainReset();
    LL_RCC_ReleaseBackupDomainReset();
    LL_RCC_LSE_Enable();
#if (USE_TIMEOUT == 1)
    Timeout = LSE_TIMEOUT_VALUE;
#endif /* USE_TIMEOUT */
    while (LL_RCC_LSE_IsReady() != 1)
    {
#if (USE_TIMEOUT == 1)
      if (LL_SYSTICK_IsActiveCounterFlag()) 
      {
        Timeout --;
      }
      if (Timeout == 0)
      {
        /* LSE activation error */
        LED_Blinking(LED_BLINK_ERROR);
      }  
#endif /* USE_TIMEOUT */
    }
    LL_RCC_SetRTCClockSource(LL_RCC_RTC_CLKSOURCE_LSE);
    
    /*##-3- Enable RTC peripheral Clocks #######################################*/
    /* Enable RTC Clock */ 
    LL_RCC_EnableRTC();
  }
#elif defined(RTC_CLOCK_SOURCE_LSI)
  /* Enable LSI */
  LL_RCC_LSI_Enable();
#if (USE_TIMEOUT == 1)
  Timeout = LSI_TIMEOUT_VALUE;
#endif /* USE_TIMEOUT */
  while (LL_RCC_LSI_IsReady() != 1)
  {
#if (USE_TIMEOUT == 1)
    if (LL_SYSTICK_IsActiveCounterFlag()) 
    {
      Timeout --;
    }
    if (Timeout == 0)
    {
      /* LSI activation error */
      LED_Blinking(LED_BLINK_ERROR);
    }  
#endif /* USE_TIMEOUT */
  }
  LL_RCC_ForceBackupDomainReset();
  LL_RCC_ReleaseBackupDomainReset();
  LL_RCC_SetRTCClockSource(LL_RCC_RTC_CLKSOURCE_LSI);

  /*##-3- Enable RTC peripheral Clocks #######################################*/
  /* Enable RTC Clock */ 
  LL_RCC_EnableRTC();

#else
#error "configure clock for RTC"
#endif

  /*##-4 Configure RTC ######################################################*/
  /* Configure RTC prescaler and RTC data registers */
  if (LL_RTC_DeInit(RTC) != SUCCESS) 
  {
    /* Initialization Error */
    LED_Blinking(LED_BLINK_ERROR);
  }

  /* Set fields of initialization structure:
      - Hour Format    = Format 12
      - Asynch Prediv  = Value according to source clock
      - Synch Prediv   = Value according to source clock
  */
  rtc_initstruct.HourFormat      = LL_RTC_HOURFORMAT_AMPM;
  rtc_initstruct.AsynchPrescaler = RTC_ASYNCH_PREDIV;
  rtc_initstruct.SynchPrescaler  = RTC_SYNCH_PREDIV;

  /* Initialize RTC instance according to parameters defined in initialization structure. */  
  if (LL_RTC_Init(RTC, &rtc_initstruct) != SUCCESS)
  {
    /* Initialization Error */
    LED_Blinking(LED_BLINK_ERROR);
  }
}

/**
  * @brief Configure the current time and date and set alarm.
  * Note   __LL_RTC_CONVERT_BIN2BCD helper macro can be used if user wants to
  *        provide directly the decimal value:                               
  *        LL_RTC_DATE_Config(RTC, LL_RTC_WEEKDAY_MONDAY,                    
  *                          __LL_RTC_CONVERT_BIN2BCD(31), (...))           
  * @param  None
  * @retval None
  */
void Configure_RTC_Alarm(void)
{
  LL_RTC_DateTypeDef rtc_date_initstruct;
  LL_RTC_TimeTypeDef rtc_time_initstruct;
  LL_RTC_AlarmTypeDef rtc_alarm_initstruct;
  
  /*## Configure the Date ################################################*/
  /* Set Date: Monday March 31th 2015 */
  rtc_date_initstruct.WeekDay = LL_RTC_WEEKDAY_MONDAY;
  rtc_date_initstruct.Day     = 0x31;
  rtc_date_initstruct.Month   = LL_RTC_MONTH_MARCH;
  rtc_date_initstruct.Year    = 0x15;

  /* Initialize RTC date according to parameters defined in initialization structure. */  
  if (LL_RTC_DATE_Init(RTC, LL_RTC_FORMAT_BCD, &rtc_date_initstruct) != SUCCESS)   
  {
    /* Initialization Error */
    LED_Blinking(LED_BLINK_ERROR);
  }

  /*## Configure the Time ################################################*/
  /* Set Time: 11:59:55 PM*/
  rtc_time_initstruct.TimeFormat = LL_RTC_TIME_FORMAT_PM;
  rtc_time_initstruct.Hours      = 0x11;
  rtc_time_initstruct.Minutes    = 0x59;
  rtc_time_initstruct.Seconds    = 0x55;

  /* Initialize RTC time according to parameters defined in initialization structure. */  
  if (LL_RTC_TIME_Init(RTC, LL_RTC_FORMAT_BCD, &rtc_time_initstruct) != SUCCESS)   
  {
    /* Initialization Error */
    LED_Blinking(LED_BLINK_ERROR);
  }
  
  /*## Configure the RTC Alarm peripheral #################################*/
  /* Set Alarm to 12:00:25 */
  rtc_alarm_initstruct.AlarmTime.TimeFormat = LL_RTC_ALMA_TIME_FORMAT_AM;
  rtc_alarm_initstruct.AlarmTime.Hours      = 0x12;
  rtc_alarm_initstruct.AlarmTime.Minutes    = 0x00;
  rtc_alarm_initstruct.AlarmTime.Seconds    = 0x25;

  /* RTC Alarm Generation: Alarm on Hours, Minutes and Seconds (ignore date/weekday)*/
  rtc_alarm_initstruct.AlarmMask            = LL_RTC_ALMA_MASK_DATEWEEKDAY;
  rtc_alarm_initstruct.AlarmDateWeekDaySel  = LL_RTC_ALMA_DATEWEEKDAYSEL_DATE;
  rtc_alarm_initstruct.AlarmDateWeekDay     = 0x01;

  /* Initialize ALARM A according to parameters defined in initialization structure. */  
  if (LL_RTC_ALMA_Init(RTC, LL_RTC_FORMAT_BCD, &rtc_alarm_initstruct) != SUCCESS)   
  {
    /* Initialization Error */
    LED_Blinking(LED_BLINK_ERROR);
  }

  /* Disable the write protection for RTC registers */
  LL_RTC_DisableWriteProtection(RTC);

 /* Enable Alarm*/
  LL_RTC_ALMA_Enable(RTC);

 /* Clear the Alarm interrupt pending bit */
  LL_RTC_ClearFlag_ALRA(RTC);
  
  /* Enable IT Alarm */
  LL_RTC_EnableIT_ALRA(RTC);

  /* Enable the write protection for RTC registers */
  LL_RTC_EnableWriteProtection(RTC);

   /* RTC Alarm Interrupt Configuration: EXTI configuration */
  LL_EXTI_EnableIT_0_31(LL_EXTI_LINE_17);
  LL_EXTI_EnableRisingTrig_0_31(LL_EXTI_LINE_17);
  
  /*## Configure the NVIC for RTC Alarm ##################################*/
  NVIC_SetPriority(RTC_Alarm_IRQn, 0x0F);
  NVIC_EnableIRQ(RTC_Alarm_IRQn);
}

/**
  * @brief  Display the current time and date.
  * @param  None
  * @retval None
  */
void Show_RTC_Calendar(void)
{
  /* Note: need to convert in decimal value in using __LL_RTC_CONVERT_BCD2BIN helper macro */
  /* Display time Format : hh:mm:ss */
  sprintf((char*)aShowTime,"%.2d:%.2d:%.2d", __LL_RTC_CONVERT_BCD2BIN(LL_RTC_TIME_GetHour(RTC)), 
          __LL_RTC_CONVERT_BCD2BIN(LL_RTC_TIME_GetMinute(RTC)), 
          __LL_RTC_CONVERT_BCD2BIN(LL_RTC_TIME_GetSecond(RTC)));
  /* Display date Format : mm-dd-yy */
  sprintf((char*)aShowDate,"%.2d-%.2d-%.2d", __LL_RTC_CONVERT_BCD2BIN(LL_RTC_DATE_GetMonth(RTC)), 
          __LL_RTC_CONVERT_BCD2BIN(LL_RTC_DATE_GetDay(RTC)), 
          2000 + __LL_RTC_CONVERT_BCD2BIN(LL_RTC_DATE_GetYear(RTC)));
} 

/**
  * @brief  Initialize LED2.
  * @param  None
  * @retval None
  */
void LED_Init(void)
{
  /* Enable the LED2 Clock */
  LED2_GPIO_CLK_ENABLE();

  /* Configure IO in output push-pull mode to drive external LED2 */
  LL_GPIO_SetPinMode(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_MODE_OUTPUT);
  /* Reset value is LL_GPIO_OUTPUT_PUSHPULL */
  //LL_GPIO_SetPinOutputType(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_OUTPUT_PUSHPULL);
  /* Reset value is LL_GPIO_SPEED_FREQ_LOW */
  //LL_GPIO_SetPinSpeed(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_SPEED_FREQ_LOW);
  /* Reset value is LL_GPIO_PULL_NO */
  //LL_GPIO_SetPinPull(LED2_GPIO_PORT, LED2_PIN, LL_GPIO_PULL_NO);
}

/**
  * @brief  Turn-on LED2.
  * @param  None
  * @retval None
  */
void LED_On(void)
{
  /* Turn LED2 on */
  LL_GPIO_SetOutputPin(LED2_GPIO_PORT, LED2_PIN);
}

/**
  * @brief  Set LED2 to Blinking mode for an infinite loop (toggle period based on value provided as input parameter).
  * @param  Period : Period of time (in ms) between each togg ling of LED
  *   This parameter can be user defined values. Pre-defined values used in that example are :
  *     @arg LED_BLINK_FAST : Fast Blinking
  *     @arg LED_BLINK_SLOW : Slow Blinking
  *     @arg LED_BLINK_ERROR : Error specific Blinking
  * @retval None
  */
void LED_Blinking(uint32_t Period)
{
  /* Toggle IO in an infinite loop */
  while (1)
  {
    LL_GPIO_TogglePin(LED2_GPIO_PORT, LED2_PIN);  
    LL_mDelay(Period);
  }
}

/**
  * @brief  System Clock Configuration
  *         The system Clock is configured as follow :
  *            System Clock source            = PLL (HSI)
  *            SYSCLK(Hz)                     = 32000000
  *            HCLK(Hz)                       = 32000000
  *            AHB Prescaler                  = 1
  *            APB1 Prescaler                 = 1
  *            APB2 Prescaler                 = 1
  *            HSI Frequency(Hz)              = 16000000
  *            PLLMUL                         = 6
  *            PLLDIV                         = 3
  *            Flash Latency(WS)              = 1
  * @retval None
  */
void SystemClock_Config(void)
{
  /* Enable ACC64 access and set FLASH latency */ 
  LL_FLASH_Enable64bitAccess();; 
  LL_FLASH_SetLatency(LL_FLASH_LATENCY_1);

  /* Set Voltage scale1 as MCU will run at 32MHz */
  LL_APB1_GRP1_EnableClock(LL_APB1_GRP1_PERIPH_PWR);
  LL_PWR_SetRegulVoltageScaling(LL_PWR_REGU_VOLTAGE_SCALE1);
  
  /* Poll VOSF bit of in PWR_CSR. Wait until it is reset to 0 */
  while (LL_PWR_IsActiveFlag_VOSF() != 0)
  {
  };
  
  /* Enable HSI if not already activated*/
  if (LL_RCC_HSI_IsReady() == 0)
  {
    /* HSI configuration and activation */
    LL_RCC_HSI_Enable();
    while(LL_RCC_HSI_IsReady() != 1)
    {
    };
  }
  
  /* Main PLL configuration and activation */
  LL_RCC_PLL_ConfigDomain_SYS(LL_RCC_PLLSOURCE_HSI, LL_RCC_PLL_MUL_6, LL_RCC_PLL_DIV_3);

  LL_RCC_PLL_Enable();
  while(LL_RCC_PLL_IsReady() != 1)
  {
  };
  
  /* Sysclk activation on the main PLL */
  LL_RCC_SetAHBPrescaler(LL_RCC_SYSCLK_DIV_1);
  LL_RCC_SetSysClkSource(LL_RCC_SYS_CLKSOURCE_PLL);
  while(LL_RCC_GetSysClkSource() != LL_RCC_SYS_CLKSOURCE_STATUS_PLL)
  {
  };
  
  /* Set APB1 & APB2 prescaler*/
  LL_RCC_SetAPB1Prescaler(LL_RCC_APB1_DIV_1);
  LL_RCC_SetAPB2Prescaler(LL_RCC_APB2_DIV_1);

  /* Set systick to 1ms in using frequency set to 32MHz                             */
  /* This frequency can be calculated through LL RCC macro                          */
  /* ex: __LL_RCC_CALC_PLLCLK_FREQ (HSI_VALUE, LL_RCC_PLL_MUL_6, LL_RCC_PLL_DIV_3); */
  LL_Init1msTick(32000000);
  
  /* Update CMSIS variable (which can be updated also through SystemCoreClockUpdate function) */
  LL_SetSystemCoreClock(32000000);
}

/******************************************************************************/
/*   USER IRQ HANDLER TREATMENT                                               */
/******************************************************************************/
/**
  * @brief  Alarm callback
  * @param  None
  * @retval None
  */
void Alarm_Callback(void)
{
  /* Turn LED2 on: Alarm generation */
  LED_On();
}

#ifdef  USE_FULL_ASSERT

/**
  * @brief  Reports the name of the source file and the source line number
  *         where the assert_param error has occurred.
  * @param  file: pointer to the source file name
  * @param  line: assert_param error line source number
  * @retval None
  */
void assert_failed(uint8_t *file, uint32_t line)
{
  /* User can add his own implementation to report the file name and line number,
     ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */

  /* Infinite loop */
  while (1)
  {
  }
}
#endif

/**
  * @}
  */

/**
  * @}
  */

/************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
